Sodium Thiosulfate → tert-butyl (2S)-7-bromo-2-methyl-8-(1-methylethyl)-2,3-dihydrothieno[2,3-f][1,4]oxazepine-4(5H)-carboxylate

Participants

Reaction Steps

A solution of tert-butyl (2S)-2-methyl-8-(1-methylethyl)-2,3-dihydrothieno[2,3-f][1,4]oxazepine-4(5H)-carboxylate (839 mg) obtained in Example 15, step 1, N-bromosuccinimide (503 mg) and acetonitrile (10 mL) was stirred at room temperature for 1.5 hr, 10% aqueous sodium thiosulfate solution was added, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (solvent gradient; 3→7% ethyl acetate/hexane) to give the title compound (908 mg, 86%) as a solid.

Provenance & Evidence